tegrakernel/kernel/kernel-4.9/arch/um/drivers/ubd_user.c

60 lines
1.1 KiB
C

/*
* Copyright (C) 2000, 2001, 2002 Jeff Dike (jdike@karaya.com)
* Copyright (C) 2001 Ridgerun,Inc (glonnon@ridgerun.com)
* Licensed under the GPL
*/
#include <stddef.h>
#include <unistd.h>
#include <errno.h>
#include <sched.h>
#include <signal.h>
#include <string.h>
#include <netinet/in.h>
#include <sys/time.h>
#include <sys/socket.h>
#include <sys/mman.h>
#include <sys/param.h>
#include <endian.h>
#include <byteswap.h>
#include "ubd.h"
#include <os.h>
int start_io_thread(unsigned long sp, int *fd_out)
{
int pid, fds[2], err;
err = os_pipe(fds, 1, 1);
if(err < 0){
printk("start_io_thread - os_pipe failed, err = %d\n", -err);
goto out;
}
kernel_fd = fds[0];
*fd_out = fds[1];
err = os_set_fd_block(*fd_out, 0);
if (err) {
printk("start_io_thread - failed to set nonblocking I/O.\n");
goto out_close;
}
pid = clone(io_thread, (void *) sp, CLONE_FILES | CLONE_VM, NULL);
if(pid < 0){
err = -errno;
printk("start_io_thread - clone failed : errno = %d\n", errno);
goto out_close;
}
return(pid);
out_close:
os_close_file(fds[0]);
os_close_file(fds[1]);
kernel_fd = -1;
*fd_out = -1;
out:
return err;
}